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Tylenchocriconema alleni n.g.n.sp, is described from soil about roots of a bromeliad from Guatemala City, Guatemala. It has characteristics of both the Tylenchoidea and Criconematoidea. Tylenchocriconematidae, n. fam., and Tylenchocriconematoidea, n. superfam., are proposed to express the relationship of this species to other taxa. Tylenchulidae and Paratylenchidae are considered closely related, and Tylenchulidoidea, n. rank, is proposed to indicate their relationship.  相似文献   

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The parabasalian symbionts of lower termite hindgut communities are well-known for their large size and structural complexity. The most complex forms evolved multiple times independently from smaller and simpler flagellates, but we know little of the diversity of these small flagellates or their phylogenetic relationships to more complex lineages. To understand the true diversity of Parabasalia and how their unique cellular complexity arose, more data from smaller and simpler flagellates are needed. Here, we describe two new genera of small-to-intermediate size and complexity, represented by the type species Cthulhu macrofasciculumque and Cthylla microfasciculumque from Prorhinotermes simplex and Reticulitermes virginicus, respectively (both hosts confirmed by DNA barcoding). Both genera have a single anterior nucleus embeded in a robust protruding axostyle, and an anterior bundle flagella (and likely a single posterior flagellum) that emerge slightly subanteriorly and have a distinctive beat pattern. Cthulhu is relatively large and has a distinctive bundle of over 20 flagella whereas Cthylla is smaller, has only 5 anterior flagella and closely resembles several other parababsalian genera. Molecular phylogenies based on small subunit ribosomal RNA (SSU rRNA) show both genera are related to previously unidentified environmental sequences from other termites (possibly from members of the Tricercomitidae), which all branch as sisters to the Hexamastigitae. Altogether, Cthulhu likely represents another independent origin of relatively high cellular complexity within parabasalia, and points to the need for molecular characterization of other key taxa, such as Tricercomitus.  相似文献   

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SYNOPSIS The cortical infraciliature of Kuklikophrya dragescoi gen. n., sp. n. is composed of double kinetosomes. Each kinetosome has transverse fibers. The anterior transverse fibers are associated with a sheet of dense material and the posterior transverse fibers are directed toward the posterior part of the body. The posterior kinetosome of a pair has only a short protuberance in the position of the kinetosomal fiber. The cortex has a well developed alveolar layer and a thick ecto-endoplasmic boundary. A distinctive characteristic of the buccal ciliature is the circumoral ciliature whose infraciliature is made up of pairs of cilia-bearing kinetosomes. The antero-posterior polarity of the paroral segment is in inverse relationship to that of the remaining ciliature of the organism. The adoral and preoral ciliary organelles consist of 2 rows of kinetosomes, each of which bears postciliary fibers. A frame of nematodesmata surrounds the cytopharynx which is supported by microtubular bands which impart to it a very specific laminated appearance. The “phagoplasm” is formed by “vermicelli”-like vesicles. The micronucleus is found in the perinuclear area of the macronucleus.  相似文献   

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Chitwoodius brasiliensis n.sp. is described from soil around plant roots in Vicosa, MG State, Brazil. It has a body 1.9 mm (1.6-2.5) long, odontostyle and odontophore 33 μm (31-37) and 34 μm (31-36) long, respectively, and males with spicules 59-61 μm long. Chitwoodius rusticulus n.sp. from Colombian rain forest differs from other species of the genus in having a weakly muscular anterior part of the oesophagus, a pore-like vulva, and an unsclerotized vagina. Vanderlindia venata n.sp. from lucerne soil in South Kilimanjaro, Tanzania, differs from the type and only other known species of its genus in having a smaller and less slender body (L = 3.34 mm [3.15-3.71], a = 50 [46-53]), odontostyle 2.3-2.5 times lip region width long, and stylet guiding ring located at 1.2-1.4 times lip region width from anterior end.  相似文献   

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A new sand-dwelling ciliate, Discotricha papillifera n.g., n.sp., is described and allocated to the trichostome family Trichopelmidae. The species seems to be one of the most highly differentiated members of the family. The peculiar type of its body ciliature and of its buccal structures suggests affinities with certain other major groups of ciliated protozoa; from an evolutionary point of view the organism appears to show close relationship to the gymnostome family Chlamydodontidae.  相似文献   

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SYNOPSIS Four new eimerian species are described from red-backed voles. Clethrionomys gapperi in Pennsylvania. Sporulated oocysts of Eimeria clethrionomyis sp. n. are ellipsoidal, 18.8 (16.5–21.5) × 14.9 (14.0–16.5) with elongate, ovoid sporocysts, 10.6 (9.5–12.0) × 6.1 (5.5–7.0). The oocyst wall is smooth, with 2 layers, and thins, with terminal cap at one or both ends. Polar granules, dark Stieda body and sporocyst residuum are present. The occyst residuum is absent. Sporulated oocysts of Eimeria gallatii sp. n. are ellipsoidal, 27.7 (21–32) × 19.3 (17–24) with ovoid sporocysts, 13.5 (12–15) × 8.8 (8–10). The oocyst wall is smooth, 2-layered, with a micropyle and thin wall at the end opposite the micropyle. Polar granules. Stieda body and sporocyst residuum are present. The oocyst residuum is atypical, of cobwebby material. Sporulated oocysts of Eimeria pileata sp. n. are subspherical to spherical, 25.2 (20.5–29.5) × 22.5(19.5–25.5) with ellipsoidal sporocysts, 13.4(10.5–15.0) × 8.4 (7.5–9.5). The oocyst wall is rough, pitted, striated, 2-layered, with no micropyle. Polar granules, oocyst and sporocyst residuum. Stieda body and stiedal cap are present. Sporulated oocysts of Eimeria marconii sp. n. are ellipsoidal, 13.0 (10.5–15.0) × 10.6 (9.5–12.0) with elongate, ovoid sporocysts, 7.7 (7.0–8.5) × 4.2 (3.0–4.5). The oocyst wall is smooth, single-layered, with no micropyle. Polar granules, dark Stieda body and sporocyst residuum are present. There is no oocyst residuum.  相似文献   

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Paktylenchus tuberosus gen.n., sp.n. is described and illustrated from soil around Solanum tuberosum from Kaghan Valley, Pakistan. Paktylenchus gen.n, can be distinguished from the most closely related genus, Agelenchus Andrassy, 1954, by the distinct longitudinal striae, three incisures in the lateral field, and absence of males. Paktylenchus tuberosus shows affinities to Coslenchus Siddiqi, 1978 but differs in having an oblique vagina-to-body axis and a prominent sunken vulva with vulval flaps. Four genera of the subfamily Tylenchinae are also discussed herein.  相似文献   

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Discocriconemella inaratus n. sp. from Iowa prairies is characterized by a single offset disk-shaped head annule which is often discontinuous, a sigmoid vagina, a stylet length of 51-61 μm, and 77-100 smooth body annules. Criconemoides inusitatus n. sp. from Iowa woodlands is characterized by two offset head annules, a "closed" vulva, a straight vagina, no overlapping anterior vulva lip, a stylet length of 42-50 μm, and 71-86 smooth body annules.  相似文献   

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Background

Gerontology research shows the importance of physical exercise for active aging. This study demonstrates the relationship between the practice of aerobic exercise, and physical fitness (muscle strength, respiratory capacity and motor speed) and cognitive performance (memory and visual-perceptual speed) and analyzes whether age is a modulating factor of this relationship.

Material and methods

The sample included 690 subjects with an age range of 30-85 years. The level of physical exercise was assessed using self-report form. Two sub-scales were used for the evaluation of cognitive performance: Digit Span Backwards and Digit Symbol (both are sub-scales of the Wechsler Adult Intelligence Scale - WAIS). The physical fitness was assessed using bio-behavioral measurements (strength, lung capacity, speed). To test the combined effect of exercise and age on the two variables (physical fitness and cognitive performance) two separate factorial analysis of variance were performed (procedure - general linear model: Univariate).

Result

The most significant result showed that scores on cognitive performance is a function of the intensity of the physical activity (F=4.8; P<0.002). With regard to physical fitness, its relationship with physical exercise is also significant (F=4.10; P<0.007) as well as the interaction between exercise and age (F=2.2; P<0.001).

Conclusions

The intensity in achieving aerobic exercise is associated with physical fitness and cognitive performance. Age has a specific weight in the association between exercise and physical fitness, this effect is higher in the older age groups (65-74 and 75-85 years for 30-49 and 50-64 years). These data suggest the compensatory effect of exercise on decline in old age.  相似文献   

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